That is almost as disgusting as a douche bag. Must be a SERIOUS cheap alcoholic. I used to bring booze on all time....and so do many other passengers. My Dad used to bring a case of beer in each suit case. I'm diamond on RCI and he's Diamond plus. It's not that we can't afford to buy it onboard and on top of that we get free drinks anyway due to our status. It was mainly the convienence. I like a glass of wine while I'm doing my hair & getting dressed. I don't want to wait for room service to bring it.
As a TA I can order a bottle or two for my cabin at a big discount so I no longer smuggle it onboard. Dad books suites now so he has quicker service and Mom doesn't want him drinking all the beer anyway. There are much easier ways to do it. I see it all the time.